Alarm.



J. POLO.

ALABM.

APPLICATION FILED 38.28 1014 Patented Mar. 23, 1915.

J B POLO l/vbtnemo Muck JOSEPH B. POLO, OF CLEAR LAKE, SOUTH DAKOTA.

ALARM.

Specification of Letters Patent.

Patented Mar. 23, 1915.

Application filed February 28, 1914. Serial No. 821,721.

To all whom it may concern:

Be it known that LJosErn: B. PoLo,a citizen of the United States, residing at Clear Lake, in the county of Deuel and of South Dakota, have invented certain new and useful Improvements in Alarms, of which the following is a specificat on, reference being had to the accompanying drawings.

This invention comprehends certain new and useful improvements in alarms, and relates specifically to improvements upon the form of alarm covered by my pending application, Serial No. 740.2%9, and has tor its primary object to provide a pneumatic tire alarm which will be automatic, as Well as highly cfiicient in operation.

Another obiect of the invention is to provide an alarm of this character which may be readily regulated to give an audible signal when the air pressure within the tire to which the device is connected, decreases a redetermined extent.

A further obiect is to provide an alarm of this .character which may be readily adjusted after giving a signal to give a second signal upon further decrease oi. the air pressure within the tire.

A. still further object to generally improve and simplify the construction and operation ot'devices of this character and construct the same of the minimum number of pzirts of simple f mation.

With the above and other ohiccts in view, mv invention consists in certain novel const ructions. combinations. and arrangements of parts to be hereinafter more fully described. claimed, and illustrated in the accompanying; dravvin gzs in which,

- Figure l is a sectional view taken through a device constructed in accordance with my invention. a portion of the (Io-acting tire valve and a DIOiQCtlIlg sleeve being also shown in section; and Fig. view taken substantially on the line Fig. 1.

Referring more ings in which siznilar specifically to the drawneterence characters designate corrcspta'uling parts throughout the several views. 1 designates a valve stem of the ordinary form employed in connection with pneumatic tires and surrounded bv a protecting sleeve 52 which may be sociired to the wheel telly not shovvn), in any suitable manner. Within the valve stem 1 is located the ordinary check valve 3 and 2 is a sectional I it will be noted that the free extremity l of the valve stem is reduced and threaded. Engaged upon the threaded reduced extremity 4 of the valve stem 1, is theinner end 5 of the casing- 6, the protecting sleeve 2 surrounding and protecting the connected ends of the valve stem and casin The casing 6 has a chamber 7 in its main portion and the outer end of the chamber is closed by the cap 8 threaded in the outer end of said casing. The outer portion of the chamber 7 is interiorly threaded, as shown at 9, and a nut 10 is engaged with said interiorly threaded portion of the chamher and has a reduced sleeve portion 11' hearing against the smooth sleeve 1'). which serves to clamp the circular edge of the rubber diaphragm 13 against the inner wall ll of the chamber 7.

The reduced threaded inner end t of the easing ommunicates with the chamber 7 by means of the central opening 1.5 in the inner end wall 11 of said chamber, opening is engaged the stop member 16 havin; a central passage 17 and secured centrally in the \vasner 18 formed of lead, red fiber or other suitable material in the inner end 5 of the casing. at the inner ends of the interior threads thereof. \Vhcn the device is in position upon the alve stem, the stop member 16 is engaged against the stem of the valve 3 and retains said valve in open position.

is the sliding thimble 19 which has a dependwithin which 80 and seemed ing neck portion 20 which is extended" through the center of the diaphragm and exteriorly threaded. \vherebv the nut 21 is 56- cured thereon. beneath the diaphra gm. therebv clamping the central portion of phragm to the lowerhead of the thimble. will be understood that It the head of the thimblc and neck are provided with a central open whercbv air beneath the diaphragm ing .22, may enter the thimble. as will be later clearly apparent. The head of the thimble is increased in thickness at its central portion by directing upwardly the inner wall thereof to form the valve seat 23. It will'be understood that the lower face of the head of the thimble is fiat and extended beyond the circular bodv portion 24 of 5: id thimble. which circular body portion is slidably engaged through the main portion of the nut 10. The thimble is provided with an outer circular flange 25 projecting upwardly from the said diaouter circular edge of the head and slidably engaged against the inner faces of the smooth sleeve 12 and the reduced sleeve portion 11 of the nut 10. Between the circular body portion 24 of the thimble and the ci'rcular flange 25, is positioned a helical spring 26 which has'one end bearing against the head of the 'thimble whilethe opposite end of said spring bears against the lower face of the main portion 'of said nut 10 and serves to resiliently retain thethimble in its lowermost or innermost position.

WVithinthe body 24 of the. thimble 19 and ca able ofwendwise movement therein isthe va; ve'member 27 provided at its inner or lower end witha compressible block 28,

preferably formed of rubber, adapted to be normally engaged with the'valve seat 23 and thu'seffectuall-y close the opening 22 as is believedto be self-evident. The opposite'or adjacent end of the valve member 27 is adapted to be engaged by the'head or enlargement 29 produced on the inner extremity of the rod' 30 whereby movement of the valve member 27 may be imparted in one direction, as willherein'after be self-evident. The rod 30 is directed through the bore 32 of the exteriorly threaded sleeve 33 which has adjustable en agement with the filmed openings 35 and 3 of-the cap 8 and lo nut 37, respectively. While the rod 30 is adapted to have free recurrent movement through the sleeve 33, it is to be observed that the relative transverse diameters of the rod 30 and the bore 32 are such as to afford frictional engagement between the rod 30 and the sleeve 33 whereby acertain degree of resis'tance is offered to the endwise movement I of the rod-30. As is thought to be obvious. the rod 30 is adapted to be manipulated manually and for convenience of said operation its outer or exterior extremity, as herein disclosed. is provided with a knob 31 of conventional form.

Normally the parts of my device are in the position as illustrated in Fig.1 of the accom anying drawings. the pressure of the air within the tire serving to o e come the influence of the spring 26. Should the'pressure of the air within the tire decrease from any cause, such as av puncture, to a resistive power less than the tension of the spring 26, the th mble 19 or part cularly the valve Seat 23 thereof, will be forced awav from the valve member 27 whereupon the air from within the the will enter the body portion 24 of the thimble 19, pass the valve member 27 and escape from the upper or outer end of the body portion 24 within the. c amber 7 abo e or outwardly of the nut 10. The air will then pass from the chamber 7 into the cvlinder 38 through the by-pass 39 and pass the lip 40 and escape to the atmosphere through the vent 41 into the wall of the cvlinder in close proximity to the lip 40, it being understood that the force of the air is sufficient to blow out the lu 42 positioned in said vent 41, as is clear y s own in Fig. 1,

43 which is also secured as at 44, to the ex- The plug 42 has connected therewith a chain I '70 terior of the cylinder 38, thereby eliminattling sound as is believed to be obvious. As

soon as the signal afforded by the whistle is heard, 'the rod 30 may then be operated to move the. valve member in the thimble 19, so that the block 28 carried thereby properly engages the valve seat 23, thereby preventing a continuance of the signal until there is a further decrease of the air pressure with in the tire sullicicnt to allow the helical spring 26 'to again overcome said pressure whercupon the operation herei-nbefore set forth will be repeated.

As is thought to be obvious, the pressure of the air within the tire after the first signal has been given is insuflicient to force the valve member 27 and the rod 30 upwardly or outwardly to permit said air to operate owing to the frictional engagement of the 1 rod 30 and the bore 32 of the sleeve 33. As

herein disclosed. the sleeve 33 may be read ilv adjusted and maintained in such adjusted position through the medium of the lock nut 37, such adjustment of-the sleeve serving to adiust the normal position of the head or enlargement 29 of the rod 30, therebvregulating the initial operation of the device.

It will further be understood that should it be desired to remove the alarm after the sounding of the initial signal in order to prevent all of the air from escaping from the tire through the alarm, the device may bc readily removed while exerting pressure upon the rod 30 and therebv preventing disengagement of the valve 27 from the valve seat 23.

As herein disclosed. oneend of the cylinder 3-? is open and adapted to be closed by the cap 45. This, however is not essential, but has been found preferable in the con struction of the device.

From the foregoing description, it is,

thought to be obvious that an alarm constructed in accordance with anembodimentofmy invention is of an-extrcmcly simple and comparatively inexpensive nature and is particularly well adapted for use by reason of the onvenience and facility with which it may be assembled and applied in operative position, and it will also be obvious from the foregoing description, that my alarm is susceptible of some change and modification without material departure from the principles and spirit thereof and for this reaj son I do not wish to be understood as limitizc ' ried by the casing for retaining the valve in curin open position to allow air from the valve stem to enter the casing, a dia hragm within said casing, means carrie by the diaphragm for reciprocating movement in said casing, said means having an opening whereby air within said casing may enter said means, a substantially stationary valve member within said means for preventing escape of air from said means when the latter is in normal position, signal mechae s nlsm carried by said casing, and means engaged with the second mentioned means for -moving the latter longitudinally of the casing to permit air to pass the valve member and cause operation of the signal mechanism upon decrease of the air pressure within the valve stem and easing.

2. A device of the class described comprising a casing adapted to be secured to a valve stem, means carried b the casing for retaining the valve in the va ve stem in 0 en position, a thimble within said casing. a iaphragm within said casing, means for sethe diaphragm in position, said thimb e being connected with the diaphragm and adapted to be moved thereby in one direction, a substantially stationary valve member within said thimble, said thimble having an air inlet opening, a cylinder carrie by said casing, an air passage connecting the interior of the cylinder with the interior of the casing, a lip within said cylinder adjacent said air passage, said cylinder being provided with an air (passage, said cylinder being provided with an air escape openin adjacent said lip, the air pressure from t e valve stem pressing against one face of the dia hragm and serving to retain the latter an the thimble in normal position, and means engaged with the thimble for forcing said thimble and diaphragm toward one end of the casin to permit the air to pass the valve mern er and travel into the cylinder and pass the lip to the atmosphere to give an audible signal upon decrease of the air pressure.

3. A device of the class described comprising a casing,'a diaphragm within said casing, said casing having one end open to ,pass the valve'means and ii the air pressure a permit air to enter said casing and o to H upon one face of the diaphragm to retain thl Q same in normal position, means for securing the edge of the diaphragm a inst movement, :1 thimble secured to sai diaphragm, said thimble having a circular flan surrounding its body ortion and spa from GI the same, a nut wi in said casin the body portion of said thimble being idably en-' gaged through said nut, a valve member within said thimble, said.-thimble having an air inlet opening, valve means within the thimble for engagement against the air inlet opening when said thimble is in normal position, said valve means serving to close the end of the thimble and revent air fromeseaping from said thimb e when the latter is in normal position, a cylinder connected with said casing, said cylinder havin' an air escape opening, a lip adjacent sai air esca opening, and means between the bod portion and circular flan of the-thimbe to cause movement of sai thimble and diaphragm in one direction to permit the air to to give .an audible signal upon decrease o the air pressure against the din hra 4. A device of e c h aracter described comprising a casing having a chamber in its main portion, means for closing the outer end of said casing, the inner end of said casing being reduced and adapted for engngement with a valve stem, means within said reduced inner end of the casing to retain' the valve in the valve stem in open position. a diaphra within the chamber, a thimble within said chamber and connected with the diaphra m, and provided with an opening to afl'or communication with the chamber at the opposite side of the diaphragm, means for gpiding the thimble longitudinally of the c amber, a substantially stationary valve member within said thimble, said casing hav' an air escape. opening, a lip adjacent sai 'air escape opening,

and means for forcing the thimble and diaphragm in one direction upon decrease of inst said diaphragm, said valve member ing of a transverse diameter less than the similar diameter of the bore of the thimble.

In testimony whereof I hereunto affix my 1 signature inthe presence of two witnesses JOSEPH POLO. Witnesses:

E. E. WALSETE, J. E. VALSETIIQ 

